In co-pending application Ser. No. 540,551, filed Jan. 13, 1975, assigned to the assignee of the present application, now U.S. Pat. No. 3,942,204, and elsewhere, there are disclosed single anchor leg mooring and fluid transfer devices including swivel joints for interconnection of the stationary fluid swivel center shaft pipe with a hose arm and the cargo hoses. The swivels are sealed against leakage between the swivel joint and the center shaft pipe by, for instance, Dresser gaskets, which must be packed sufficiently tightly to maintain the seal even when the swivel is deformed or wobbles slightly due to eccentricity or wear. Consequently, the seal may impose substantial resistance to rotation of the swivel joint and resultant excessive flexing of the cargo hoses in applying torque to the swivel joint or joints as the moored vessel swings around the buoy.